Ventilation system for tile roofs

ABSTRACT

A ridge vent for tile roofs is provided having a vent strip located on each side of a roof ridge. The ridge vent includes a center water dam having a centering portion and two leg portions, with the centering portion being located over a ridge board. The vent strips includes a vent material, formed from a non-woven mat, including a first surface, which matches a surface of the tile roof, and a second surface. An upper water barrier is attached to the second surface of at least one of the vent strips and extends over the roof ridge. The ridge vent is rollable and can be provided as one piece or as separate components.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/938,538, which was filed Nov. 11, 2015, will issue as U.S. Pat. No.9,803,367 on Oct. 31, 2017, and is a continuation of U.S. patentapplication Ser. No. 12/135,641, which was filed Jun. 9, 2008, is nowabandoned, and claimed the benefit of U.S. Provisional PatentApplication No. 60/942,712, filed Jun. 8, 2007. All of the foregoing areincorporated herein by reference as if fully set forth.

BACKGROUND

This invention is related to the general field of attic and roofventilation systems. It is particularly related to a roof ridgeventilating system for tile roofs.

It has been a long known practice to ventilate attics under gable roofsby running a vent along the roof ridge. Such vents are created by anopen slot running along the roof ridge, essentially the length of theroof, which causes ventilation out of the attic by convection airflowand by suction from wind blowing across the roof.

Differences between the various types of ridge vents are often found inthe capping structures used over the vent slot to exclude water andpests. Various types of ridge vents and capping structures are known inthe art. The present inventor has developed a number of novel ventingconfigurations for various asphalt, metal and tile roofs over the years.One early development used a unitary mat constructed of randomly-alignedsynthetic fibers which are joined by phenolic or latex binding agentsand heat cured to provide an air-permeable mat with a varying mesh. Capshingles are supported by the mat and are nailed directly to the roofthrough the mat. However, this arrangement does not prevent the ingressof moisture through the cap shingles that then travels into the openridge slot. The mesh is also subject to various manufacturing issues.Additionally, this earlier vent was generally only usable for flat rooftypes, and cannot be used in conjunction with contoured roofs or withheavy roofing tiles. As used herein, the phrase “heavy roofing tiles”refers to tiles made from materials which include, but are not limitedto, slate, terra cotta, concrete, and clay. These tiles aredistinguished by their bulk and weight, as contrasted to the relativelylighter shingles made of asphalt, wood, fiberglass, polymers and thelike.

The prior known vent structures useable with such heavy roofing tilesgenerally included structure to support the capping elements, which arefrequently heavy ridge cap tiles of same or similar shape andconstruction as the roof tiles, for example, as provided in theinventor's prior U.S. Pat. No. 5,326,318. However, the construction ofan assembled support from bent-up sheet metal and porous vent materialrequires shipment in fixed lengths. The cost for making and shippingthis type of vent would therefore be high. Additionally, if the rooftiles and cap tiles were “mudded” into position with cement to close thegaps between the overlapping cap tiles, as well as the gaps between thebottom of the cap tiles and the valleys of the roof field tiles alongthe roof ridge, these gaps, which were intended to remain open forventing in such prior known systems, would likely be filled with cementin accordance with customary roofing practices to prevent leaks, andtherefore block any air flow that the vent was intended to provide.

A contoured roof ridge ventilation system for metal roofs has also beendeveloped by the present inventor, and is described in U.S. Pat. No.5,561,953. This system is intended for use with metal roof panels havinga contoured surface, and provides a contoured ventilation strip coveredwith a flat cap that is nailed to the roof structure. This does notaddress tile roofs, in which not only the field of the roof iscontoured, but also the cap is cylindrical shaped and tiled, such thatthe bottoms of the cap tiles do not present an even surface, and inwhich rain driven parallel to the roof ridge may penetrate between thecap tiles.

In the inventor's prior U.S. Pat. No. 6,902,476, many of these issuesare addressed by another type of roof vent that is specifically adaptedto tile roofs, but which can still be provided in roll form that iseasily cut to length by the roofer and allows for simple installation.However, it would be desirable to ensure that no wind driven rain canpenetrate the ridge vent, even in hurricane conditions.

SUMMARY

The present invention is directed to a novel roof ridge ventilationsystem which is designed for use with heavy ridge tiles, and to a methodof venting such tiled roofs with this novel system. In particular, it isdesigned for typical tile roofs, wherein the tiles have a generallysemi-circular section profile, and are laid in rows alternatinglyinverted and overlapped with the preceding row to form an undulatingsequence of crests and gutters. The same or similar shaped tiles arethen laid along the ridge and affixed to the ridge pole to cap over thevent slot and to impart a rounded appearance to the ridge. In anotheraspect, the ridge vent can also be used for tile roofs having flat fieldtiles.

The present invention provides a ridge vent for tile roofs. The ventcomprises a center baffle that is installed over the ridge pole and avent strip located on each side of the ridge. Each vent strip includes avent material, preferably formed from a non-woven mat that includes afirst surface, which can be flat or is contoured to a profile to match aprofile of the tile roof, and a second surface. An upper water barrieris attached to the second surface and extends over the roof ridge. In analternate embodiment of the present invention, the center baffle may bereplaced with a center water dam assembly which includes additionalstrips of vent material located adjacent to either side of the ridgepole, as well as a lower water barrier attached to each side of theaddition vent strips. The ridge vent pieces can be provided separatelyor can be connected together for simpler installation.

In one assembled embodiment, the center baffle or water dam is connectedto a flexible holder that is used to connect the vent strips to oneanother. The flexible holder allows the positions of the vent strips tobe independently adjusted for alignment with the roof tiles on eitherside of the ridge. The upper water barrier overlaps both vent strips.The upper water barrier directs any moisture that passes through the captiles away from the vent slots through the roof structure. The ventassembly is rollable for easy transport, storage and use on the roof.

In another embodiment where at least some of the pieces are provided asseparate pieces, the center baffle or water dam, which is rollable, isfirst installed on the ridge pole, preferably using a temporary adhesiveand/or nails After the last course of tiles is set up to the ridge ventslot, the strips of vent material are separately installed. The upperwater barrier can be provided separately, or can be connected to one orboth of the strips of vent material.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be explained in more detail in connectionwith the drawings in which presently preferred embodiments are shown.

FIG. 1 is cross-sectional view of a first embodiment of a roof ridgevent arrangement for tile roofs in accordance with the presentinvention.

FIG. 2 is a view taken along line 2-2 in FIG. 1.

FIG. 3 is a cross-sectional view similar to FIG. 1 of a secondembodiment of a roof ridge vent arrangement for tile roofs in accordancewith the invention.

FIG. 4 is a flat pattern view of the center baffle used in the first andsecond embodiments of the invention shown in FIGS. 1 and 3.

FIG. 5 is a cross-sectional view of a stand-off molded into the centerbaffle taken along line 5-5 in FIG. 4.

FIG. 6 is a partially schematic cross-sectional view of the assembly ofthe roof ridge vent arrangement of FIG. 1 for tile roofs with agenerally flat profile.

FIG. 7 is a partially schematic cross-sectional view of the assembly ofthe roof ridge vent arrangement of FIG. 1 for tile roofs with a curvedprofile.

FIG. 8 is a flat pattern view of a flexible carrier for the vent stripsused in the embodiment of FIG. 3.

FIG. 9 is a cross-sectional view of a third embodiment of a roof ridgevent arrangement for tile roofs in accordance with the presentinvention.

FIG. 10 is a cross-sectional view of a fourth embodiment of a roof ridgevent arrangement for tile roofs in accordance with the presentinvention.

FIGS. 11, 12 a and 12 b are views of a commercial embodiment of theinvention similar to FIG. 6.

FIGS. 13, 14 a and 14 b are views of a commercial embodiment of theinvention similar to FIG. 1.

FIGS. 15, 16 a and 16 b are views of another commercial embodiment ofthe invention similar to FIG. 1.

FIG. 17 is an exploded view of a commercial embodiment of the inventionsimilar to FIG. 9.

FIG. 18 is an exploded view of a commercial embodiment of the inventionsimilar to FIG. 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Certain terminology is used in the following description for convenienceonly and is not considered limiting. Words such as “front,” “back,”“top,” and “bottom” designate directions in the drawings to whichreference is made. This terminology includes the words specificallynoted above, derivatives thereof and words of similar import.Additionally, the terms “a” and “one” are defined as including one ormore of the referenced item unless specifically noted.

The preferred embodiments of the present invention will be describedwith reference to the drawing figures, where like numerals representlike elements throughout.

Referring now to FIG. 1, a ventilation system 10 for a tile roof 12 isshown. The tile roof 12 includes a roof structure formed from roofrafters 14 that are connected to a ridge pole or beam 16. Sheathing 18may be applied over the rafters 14, as shown, and a gap or slot 20 isleft on each side of the ridge pole 16 for the ridge vent. Nailer boards19 may be located along the slots 20 for engaging the last course oftiles. Alternatively, purlins or other support structures can beutilized. The ridge pole 16 extends above the sheathing 18, or is builtup to a desired height, so that the cap shingles 30 for the tile roof 12can be affixed to it. Roofing felt or another water barrier 22 isapplied over the sheathing 18. The roof tiles 32 are then placed inposition on the roof until the final, uppermost row of tiles 32 ends ata point below the slots 20.

In a first preferred embodiment, as shown in FIG. 1, the ventilationsystem 10 is comprised of a center baffle 24 that extends over the topof the ridge pole 16 and down both sides. The center baffle 24, which isshown in a flat pattern in FIG. 4, includes a center holding strip 25that is centered over the ridge pole 16. Adhesive material 48 can bepre-applied to the center holding strip 25 to assist in assembly on theroof (FIGS. 6 and 7). Alternatively or in addition, nails can be driventhrough the center holding strip 25 into the ridge pole 16.

Baffles 26 are located on each side of the center holding strip 25, andare connected to it by connector strips 27, which generally have a widthof less than 0.25 inches and preferably have a length of at least oneinch. A fold line 28 is formed near the outer edge of each of thebaffles 26, and a flange 29 is formed across the fold line 28 as anintegral extension of each of the baffles 26. The fold line preferablyforms a pre-fold of about 45° ; however, the material of the centerbaffle 24 is preferably flexible so that the angle can be adjusted tothe particular pitch of the roof at installation. Stand-offs 31 arelocated on, formed in, or attached to the baffles 26. As shown in FIGS.4 and 5, the stand-offs 31 preferably have a depth “X” of at least 0.75inches, and more preferably have a depth X greater than or equal to oneinch. The stand-offs 31 are preferably located in each of the baffles26, and are spaced apart in a longitudinal direction (the direction ofthe roof ridge) between 6 and 15 inches, and more preferably between 9and 12 inches. Preferably the center baffle 24 is made of a polymericmaterial, such as PVC or polyethylene, and the stand-offs 31 are formedor heat pressed therein. The connector strips 27 are formed by punchingout the intermediate pieces of material. The entire center baffle 24 isflexible and rollable, allowing it to be easily carried onto a roof forinstallation and cut to the proper length so that seams can be avoided.

The center baffle 24 is preferably installed over the ridge pole 16 withthe baffles 26 extending down generally parallel to and offset from theridge pole sides due to the stand-offs 31. The flanges 29 are thenpreferably located on top of the sheathing 18 and water barrier 22, andheld in place with the uppermost nailer boards 19, adjacent to the ridgevent slots 20.

For contoured tile roofs, vent strips 38, which are formed from acontoured strip of vent material 40, are installed after the finalcourse of roof tiles 32 have been placed. The vent material 40 ispreferably a non-woven synthetic material that has a high net open freearea to allow for air passage therethrough, while acting as a filter toprevent ingress by bugs or debris. The material also generally preventsmoisture permeation, such as wind driven rain, while still allowing airflow for attic ventilation. A preferred material is disclosed in theinventor's prior U.S. Pat. No. 5,167,579. However, other suitable meshmaterials, whether woven or non-woven may be utilized.

The vent material 40 has a first surface 42 which is contoured with acomplementary profile to the roof tiles 32, and a second surface,generally opposite to the first surface that is generally flat. The ventmaterial 40 preferably has a thickness that is greater than a depth ofthe valleys in the roof tiles 32 so that it can be contoured and remainin one piece. The material 40 may be formed as a single piece, or may bemade of a plurality of pieces of material that are connected together,such as by adhesives, sewing, heat staking, heat or friction welding orfusion.

The vent material 40 is preferably adhered to the roof tiles 32 by anadhesive 52 applied to at least one of the vent material 40 and the rooftiles 32. The adhesive 52 is preferably pre-applied on the roof side ofthe vent strips 40. The adhesive 52 may include a fluid or semi-solidsubstance applied to at least one of the vent strips 38 and the rooftiles 32 during the installation process. Alternatively, the adhesive 52may include adhesive strips, of the type known in the art, suppliedpre-attached along the roof-facing surface of each vent strip 38, 38′.These adhesive strips preferably include a release strip which, whenremoved, reveals an adhesive such as acrylic or silicone.

An upper water barrier 44 is affixed to the second surface of the ventmaterial 40. For contoured tile roofs, the upper water barrier 44 iswide enough so that it will extend over the ridge pole 16 in theinstalled position, and at least partially overlaps the upper waterbarrier 44 extending from the other strip of vent material, as shown inFIG. 7. This allows the two vent strips 38 to be adjusted in thelongitudinal direction to match the contour of the tiles on each side ofthe roof.

The upper water barrier is preferably made of a closed cell foammaterial or a polyvinyl chloride or other polymeric sheet material, butmay be made from any suitable water resistant material that can beadhered to or affixed to the vent material 40, such as by an adhesive,heat staking, sewing, solvent or heat welding, or by any other suitablemeans. An adhesive material 46 may be applied to one or both sides ofthe free ends of the upper water barriers 44, so that upon installation,the upper water barriers 44 from the vent strips 38 overlap and can beadhered to one another. However, this is not required. As shown in FIG.1, preferably the upper water barrier 44 has some stiffness and is bowedoutwardly, toward the underside of the ridge cap tiles 30.

For flat tiles, as shown in FIG. 6, the vent strips 38′ do not need tobe contoured, and a single upper water barrier 44′ can be used with onevent strip being connected to each longitudinal edge. Adhesive material46 is preferably provided in the center area for connection onto thecenter holding strip 25 of the center baffle 24.

In a second preferred embodiment of the invention, shown in FIG. 3, theprofiled vent strips 40 are connected to a separate flexible carrier 50.The carrier 50, shown in FIG. 8, has a centering strip 54 which allowsassembly with the center baffle 24 and the upper water barrier 44′. Theconnector strips 56 end in attachment strips 58 along the longitudinaledges for attachment to the profiled vent strips 40. Connector strips 56are provided with a length which is sufficient to allow the contour ofeach of the profiled vent strips 40 to be aligned with the roof tiles32. The connector strips 56 are preferably at least 3 inches long andpreferably less than 0.25 inches wide. The strips 56 are preferablyspaced apart by at least 6 inches and more preferably are 12 to 15inches apart. Preferably, the flexible carrier 50 is made of a stampedor punched PVC sheet. However, other materials can be utilized. Thecenter baffle 24, the carrier 50 with the profiled vent strips 40, andthe water barrier 44 can be pre-assembled by gluing or heat stakingalong the center section that attaches to the ridge pole 18. The entireassembly remains rollable due to the flexibility of the materials.

In reference to FIG. 9, a ventilation system 110 according to a thirdpreferred embodiment of the present invention is shown. In thisembodiment, the center baffle is replaced with a center water damassembly 124. The center water dam assembly 124 includes a ridge polecap 125, vent strips 160, and lower water barriers 162. Attached to theoutward facing sides of the ridge pole cap 125 are vent strips 160,preferably comprised of a non-woven synthetic material similar to thatdescribed above with respect to the first preferred embodiment. The ventstrips 160 are preferably attached to the ridge pole cap 125 by anadhesive, or adhesive strip, applied to at least one of the vent strip160 and the ridge pole cap 125. The lower water barriers 162 are securedto the vent strips 160 on an upper portion 164 thereof, preferably by anadhesive. The water barriers 162 may also include a down-turned orhooked portion on an end of the upper portion 164 in order to moreeffectively prevent in ingress of moisture and debris. The lower waterbarriers 162 are preferably formed of a flexible material, such asstamped or punched PVC sheet, so that the angle of the flanges 166,formed in the lower water barrier, can be adjusted to fit the particularpitch of a roof.

For installation, the ridge pole cap 125 is placed over the ridge pole116 and preferably is fixed thereto by an adhesive material, nails,screws, or other suitable fastening means. The flanges 166 are placed ontop of the sheathing 118, and held in place with the nailer boards 119,adjacent to the ridge vent slot 120, in a manner similar to thatdescribed above with respect to the first embodiment of the presentinvention.

Vent strips 138 are placed on either side of the ridge vent slots 120and are preferable adhered to roof tiles 132 in the manner describedabove with respect to the first embodiment. Similarly, the vent strips138 may be joined with at least one, and preferably two, upper waterbarrier 144 in the manner described above with respect to FIGS. 6 and 7.The separate flexible carrier described in the second embodiment mayalso be utilized to connect the vent strips 138.

In a fourth embodiment of the present invention, show in FIG. 10, aridge riser bracket 170 is utilized in conjunction with the water damassembly 124 described above with respect to the third preferredembodiment of the present invention. In this embodiment, the ridge polehas been replaced with a ridge riser board 171. The ridge riser bracket170, used to support the ridge riser board 171, includes a ridge riserboard opening 172, leg portions 174, and flanges 176. The ridge riserbracket 170 is configured to be fitted into the water dam assembly 124,with the ridge riser board 171 located in the ridge riser board opening172.

Similar to the connector strips 27, 56 described in the first and secondembodiments, the leg portions 174 and the flanges 176 of the ridge riserbracket 170 preferably comprise spaced apart strips with a width ofpreferably less than 0.25 inches, which permit air flow through theridge riser bracket 170, and into the ridge gap 120. Preferably, theridge riser bracket 170 is formed from metal. The flanges 174 arepreferably secured to the roof to provide a ridge pole to connect thecap tiles.

Referring to FIGS. 1, 6, and 7, for installation of the first and secondpreferred embodiments, the center baffle 24 is first installed over theridge pole 18. After the field tiles on the roof have been laid up tothe upper course (below the vent slots 20), for the embodiment shown inFIGS. 1 and 7, the individual profiled vent strips 40 with the attachedupper water barriers 44 are then installed. The contoured surface 42 ofeach strip 38 is aligned with the complementary projections and recessesof the roof tiles 32, with the upper water barriers 44 overlapping oneanother over the ridge pole 16. For the embodiment of FIG. 6, for flattiles, the upper water barrier 44′ with the non-profiled vent strips 40′is installed as a single piece over the ridge pole. The cap tiles 30 canthen be placed to complete the installation.

As shown in FIGS. 1, the vent material 40 is partially compressed by thecap tiles 30 so that the gaps (indicated at 50 in FIG. 2) created byoverlapping cap tiles 30 are filled. Additionally, in a preferredembodiment where the vent material is at least partially formed of anon-woven synthetic fiber matting as described, for example in U.S. Pat.No. 5,167,579, the vent material 40 is preferably heated so that it“lofts” or expands and is then calendered down to a specific thicknessprior to the profiles being cut to match the roof contours. Since thematerial 40 is calendered, it can also expand somewhat due to sungenerated heat on the roof after installation in order to further fillthe gaps 50 to prevent the ingress of insects or debris.

With respect to the embodiment of FIG. 3, the entire venting assembly,including the center baffle 24, carrier 50 with profiled strips andupper water barrier 44′, is attached to the ridge pole 16, preferablywith adhesive and/or nails. The flanges 29 of the center baffle 24 areconnected to the sheathing 18, over the water barrier 22. The roof fieldtiles 32 are laid in the usual manner and the vent strips 40 and upperwater barrier 44′ are flexed upwardly to allow the final upper course oftiles 32 to be laid up to a position adjacent to the vent slots 20. Theprofiled vent strips 40 can then be longitudinally adjusted to match thecontour of the roof tiles due to the length and flexibility of theconnector strips 56. The upper water barrier 44′ remains in place, andthe cap tiles 30 can then be installed in the usual manner.

In use, the upper water barriers 44, 44′ prevent any moisture which maypermeate the seams between the overlapping ridge cap tiles 30 frompenetrating the roof structure through the slots 20. Any wind drivenmoisture that is driven up the roof slope is stopped by the ventmaterial 40, 40′ or the baffle 26, which returns any water thatpermeates the vent material 40, 40′ back down the roof. Air flow occursover the baffles 26 through the spaces between the connector strips 27,and in the embodiment of FIG. 3, also between the connector strips 56.This provides a high net free area for ventilation with superiorresistance to the ingress of moisture from wind driven rain in arollable product.

With respect to the third embodiment of the present invention shown inFIG. 9, the center water dam 124, including the ridge poll cap 125, ventstrips 160, and the lower water barriers 162, is attached to the ridgepole 116, preferably with adhesive and/or nails The flanges 166 of thelower water barriers 162 are connected to the sheathing 118 over thewater barrier 22. The individual vent strips 138 and upper water barrier144 are then installed in the same manner as described above withrespect to the first embodiment of the present invention.

The fourth embodiment of the present invention, shown in FIG. 10, isinstalled in a similar fashion. The ridge riser board 171 is fitted intothe ridge riser bracket 170. The center water dam assembly 124 is thenfitted over the ridge riser bracket 170 and the ridge riser board 171.The flanges 166, 176 of the lower water barriers 162 the ridge riserbracket 170 are connected to the sheathing 118 over the water barrier22. The installation of the vent strips 138, the remaining roof tiles132, and the cap tiles 130, is similar to that which is described abovewith respect to the first embodiments of the present invention.

In use, the third and fourth embodiments prevent moisture and debrisfrom entering the roof slot 120 in much the same manner as the previousembodiments. The upper water barrier 144 prevents any moisture which maypermeate the seams between the overlapping ridge cap tiles 130 frompenetrating the roof structure through the slots 120. Wind drivenmoisture driven up the roof slope is stopped by the vent strips 138 and160, or the lower water barrier 162. In the third embodiment depicted inFIG. 9, air flow occurs through the slots 120 and passes through thecenter water dam assembly 124 through the vent strips 160, and continuesthrough the vent strips 138. In the fourth embodiment, air flow occursagain through the slots 120, continues through the openings between theleg portions 174 and the flanges 176 of the ridge riser bracket 170,enters the water damn assembly 124 through the vent strips 160, andproceeds through the vent strips 138.

FIGS. 11, 12 a and 12 b show a commercial version of the embodiment ofFIG. 6. The water dam provided by the center baffle 25 includesadditional stand-offs 31 a for better positioning on the ridge beam.

FIGS. 13, 14 a and 14 b show a commercial version of the embodiment ofFIG. 1, with the extra standoffs 31 a on the center baffle 25.

FIGS. 15, 16 a and 16 b show a third commercial embodiment similar toFIGS. 1, 13, 14 a and 14 b. Here, the vent strips 40 have a deeperprofiling to match the roof field tiles.

FIG. 17 shows an exploded view of a commercial embodiment of theembodiment of FIG. 9. The subassembly of the center water dam 124 as aseparate part is clearly visible.

FIG. 18 shows an exploded view of a commercial embodiment of theembodiment of FIG. 10.

While the preferred embodiments of the invention have been described indetail, the invention is not limited to these specific embodimentsdescribed above which should be considered as merely exemplary. Furthermodifications and extensions of the present invention may be developedand all such modifications are deemed to be within the scope of thepresent invention as defined by the appended claims.

What is claimed is:
 1. A rollable roof ventilation system for a tileroof having a roof ridge, comprising: a center water dam assemblyconfigured to be located over a ridge board, which includes a top, afirst outward facing side, and a second outward facing side, the centerwater dam assembly comprising a ridge pole cap configured to be locatedover the top of the ridge board, a first vent strip, a second ventstrip, a first lower water barrier, and a second lower water barrier,the first vent strip configured to be disposed on the first outwardfacing side of the ridge board, the second vent strip configured to bedisposed on the second outward facing side of the ridge board, the firstlower water barrier secured to an upper portion of the first vent strip,and the second lower water barrier secured to an upper portion of thesecond vent strip; a third vent strip comprising a first surfaceconfigured to be complementary to the tile roof, and a second surfacegenerally opposite to the first surface; a fourth vent strip configuredto be located generally parallel to the first vent strip and on anopposite side of the roof ridge with respect to the first vent strip,and comprising a first surface configured to be complementary to thetile roof, and a second surface generally opposite to the first surface;and at least one upper water barrier connected to at least one of thesecond surface of the third vent strip and the second surface of thefourth vent strip, and extending therefrom toward the roof ridge.
 2. Theroof ventilation system of claim 1, wherein at least one of the firstvent strip, the second vent strip, the third vent strip, and the fourthvent strip are comprised of a non-woven synthetic material.
 3. The roofventilation system of claim 1, wherein at least one of the first lowerwater barrier and the second lower water barrier are comprised ofpolyvinyl chloride sheet material.
 4. The roof ventilation system ofclaim 1, wherein the at least one upper water barrier is comprised ofclosed cell foam, polyvinyl chloride, or polymeric sheet material. 5.The roof ventilation system of claim 1, wherein the at least one upperwater barrier includes first and second water barriers attached to thethird vent strip and fourth vent strip, respectively, each of the firstand second water barriers extending from a respective vent strip overthe top of the ridge board and toward each other and each of the firstand second water barriers including respective free ends that overlapeach other over the top of the ridge board.
 6. The roof ventilationsystem of claim 1, wherein the at least one upper water barriercomprises a single water barrier comprising a first end that is attachedto the third vent strip, and a second end that is in contact with thefourth vent strip.
 7. The roof ventilation system of claim 1, whereinthe at least one upper water barrier comprises a single water barrier,and a first end of the single water barrier is attached to the thirdvent strip, and a second end of the single water barrier is configuredto be connected to the fourth vent strip.
 8. The roof ventilation systemof claim 1, further comprising at least one ridge cap tile configured tobe placed on the roof ridge, wherein first and second edges of the ridgecap tile are configured to rest on at least a portion of the secondsurface of the third vent strip and the second surface of the fourthvent strip, respectively.
 9. The roof ventilation system of claim 1,wherein the third vent strip and the fourth vent strip includecontouring on the respective first surfaces for mating withcomplementing contouring of the tile roof.
 10. The roof ventilationsystem of claim 1, further comprising a flexible carrier attachedbetween the third vent strip and the fourth vent strip.
 11. A method ofimproving ventilation to a building comprising a roof including at leastone vent slot disposed along a ridge board, which includes a top, afirst outward facing side, and a second outward facing side, and aplurality of mating tiles overlying the roof, the method comprising:applying a center water dam assembly over the ridge board, the centerwater dam assembly comprising a ridge pole cap located over the top ofthe ridge board, a first vent strip, a second vent strip, a first lowerwater barrier, and a second lower water barrier, the first vent stripdisposed on the first outward facing side of the ridge board, the secondvent strip disposed on the second outward facing side of the ridgeboard, the first lower water barrier secured to an upper portion of thefirst vent strip, and the second lower water barrier secured to an upperportion of the second vent strip.
 12. The method of claim 11 furthercomprising applying: a third vent strip to the tile roof, the third ventstrip comprising a first surface complementary to the tile roof and asecond surface generally opposite to the first surface; and a fourthvent strip to the tile roof generally parallel to the first vent stripand on an opposite side of the roof ridge with respect to the first ventstrip, the fourth vent strip comprising a first surface configured to becomplementary to the tile roof, and a second surface generally oppositeto the first surface.
 13. The method of claim 12 further comprisingapplying at least one upper water barrier connected to at least one ofthe second surface of the third vent strip and the second surface of thefourth vent strip, and extending therefrom toward the roof ridge. 14.The method of claim 13 further comprising connecting a free end of thefirst water barrier to the second surface of the second vent strip. 15.The method of claim 14, wherein the step of connecting the free end ofthe first water barrier includes attaching the free end of the waterbarrier to the second surface of the second vent strip by an adhesiveapplied to at least one of the second surface of the second vent stripand the free end of the water barrier.
 16. The method of claim 13,further comprising the step of positioning free ends of the first andsecond upper water barriers on the ridge board.
 17. The method of claim16, further comprising the step of attaching the free end of the firstupper water barrier to the free end of the second upper water barrier.18. The method of claim 13 further comprising connecting at least oneridge cap tile comprising first and second ends to the roof along theroof ridge, wherein the first and second ends of the ridge cap tile reston respective portions of the second surfaces of the third and fourthvent strips.
 19. The method of claim 13, wherein at least one of thefirst vent strip, the second vent strip, the third vent strip, and thefourth vent strip are comprised of a non-woven synthetic material. 20.The method of claim 19, wherein at least one of the first lower waterbarrier and the second lower water barrier are comprised of polyvinylchloride sheet material.